Vivian Edmonds was 72 years old when Columbine High School massacre: Eric Harris and Dylan Klebold killed 13 people and injured 24 others before committing suicide at Columbine High School in Columbine, Colorado. The Columbine High School massacre was a school shooting that occurred on April 20, 1999, at Columbine High School in Columbine, an unincorporated area of Jefferson County, Colorado, United States, in the Denver metropolitan area. In addition to the shootings, the complex and highly planned attack involved a fire bomb to divert firefighters, propane tanks converted to bombs placed in the cafeteria, 99 explosive devices, and car bombs. The perpetrators, senior students Eric Harris and Dylan Klebold, murdered 12 students and one teacher. They injured 21 additional people, and three more were injured while attempting to escape the school. The pair subsequently committed suicide.